Prefabricated window and frame structure having removable sash-balanced window panels



March 10, 1970 H. BAER 3,499,248

PREFABRICATED WINDOW AND FRAME STRUCTURE HAVING REMOVABLE SASH-BALANCED WINDOW PANELS Flled Feb 26 1968 4 Sheets-Sheet 1 INVENTOR. Haws IBM-1e FIG. l

H. BAER 3,499,248 PREFABRICATED WINDOW AND FRAME STRUCTURE HAVING March 10, 1970 4 SheetsSheet 2 REMOVABLE SASH-BALANCED WINDOW PANELS Filed Feb. 26. 1968 FIG. 6

FIG.

INVENTOR. HAMS BAY-5Q QxWeM ATPQKNQI March 10, 1970 H. BAER 3,499,248

PREFABRICATED WINDOW AND FRAME STRUCTURE HAVING REMOVABLE SASH-BALANCED WINDOW P/KNFLS Filed Feb. 26, 1968 4 Sheets-Sheet 3 INVENTOR. HAns Base W WM (Aw-ma a:

March 10, 1970 H. BAER 3,499,248

PREFABRICATED WINDOW AND FRAME STRUCTURE HAVING REMOVABLE SASH-BALANCED WINDOW PANELS Filed Feb. 26, 1968 4 Sheets-Sheet 4 INVENTOR. Hmos BAER MW M ATRQRMEK) United States Patent 3,499 248 PREFABRICATED WINDO W AND FRAME STRUC- TURE HAVING REMOVABLE SASH-BALANCED WINDOW PANELS Hans Baer, 4 Vermont Ave., Toronto, Ontario, Canada Filed Feb. 26, 1968, Ser. No. 708,392 Int. Cl. E05d 13/12; E06]: 3/44 US. Cl. 49430 10 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION According to present day construction methods and techniques, sash-type window and frame structures are commonly preconstructed, or prefabricated, and installed as tailored units in a building-wall window opening. Such construction methods and techniques are generally applicable to prime window units or combination-type storm and screen units. By utilizing preconstructed, or prefabricated, window and frame units, it has been found that a substantial reduction in installation and construction time, as well as cost, can ordinarily be achieved since such units tend to minimize the extent of labor and customized construction and assembly normally heretofore required at the site of installation. However, many of such prefabricated or package-types of window and frame units, when installed, either fail to provide adequate alignment and close-fitting interrelationship and cooperation between the assembled window and frame components, or else the assembled components tend to bind and restrict the desired smooth sliding movement of the window or screen panels within the frame.

Heretofore, the various structural concepts employed in providing prefabricated window and frame installations have been predominantly of such a character that, although a portion of the assembly was susceptible to being prefabricated and preassembled prior to installation, a considerable extent of the assemblement, arrangement and alignment of the various structural components of the window and particularly the frame structure had to be completed at the time of installation in order to effect a proper organization and orientation of the frame and panel components. As a consequence, prior to installation of the window and frame structure, it was ordinarily impossible to obtain, or fabricate, a frame having a structure sufficiently complete and stable that the frame itself, even when properly arranged with the building-wall window opening, could be relied upon to provide proper overall alignment and orientation for the panel components of the assembly. Consequently, time consuming and costly adjustment of various sections of the frame was required. Therefore, considerable effort has been expended in attempting to prefabricate an essentially unitary frame structure capable of obviating or greatly minimizing the extent of assembly and/or adjustment of the frame required during installation. Such efforts, however, have ordinarily left much to be desired in that they have, of necessity, usually resulted in the fabrication of a composite unit which was not suited to the inclusion of various other desirable features. For example, prefabricated, unitary frame structures heretofore utilized have generally been of such a construction as to render it difficult to readily remove the window or screen panels from the frame for such temporary purposes as cleaning and repair. Also, such rigid frame units characteristically lack the requisite close-fitting precision necessary to afford a highly effective weather or insect barrier restricting the interspaces allotted for relative overlapping movement between the panels.

Moreover, previous prefabricated window and frame structures by virtue of design limitations and cost considerations have been characteristically devoid of such desirable structural features as sash balances which provide a counterbalancing of the weight of the sash panels and facilitate substantially effortless movements of the sash panels to and between selectively variable open and closed assembled positions, as well as permitting the sash panels to resist the gravitational tendency to always shift or fall downward within the frame structure. Consequently, such sash panels are generally provided with less desirable spring actuated finger locks which when released snap marginally outward from the sash panels and into counterpart openings provided therefor in various spaced locations arranged along the length of the guide track. Hence, the various open and closed positions of each of the sash panels are restricted to positions coinciding with the locations at which the finger locks may be received within the openings provided in the guide tracks. Nonetheless, the variability in positioning of the window is substantially restricted by the use of such finger locks. Moreover, finger locks do not avoid the weight problem encountered in manually raising or shifting large window panels and particularly large window panels of the size frequently employed in ofiice buildings.

Keeping in mind both the advantageous and disadvantageous aspect of preconstructed, or prefabricated, sashtype prime window and frame units, it will be appreciated from the ensuing description that the present invention pertains to structural innovations in sliding or sash-type window and frame structures which, in addition to being adaptable to customized, or non-prefabricated, constructions, are particularly well-suited for use in conjunction With various types of prefabricated prime window and frame units, including prefabricated, framed combination storm window and screen units and most especially prefabricated prime window and frame units such as may be utilized both in new home and building construction and in replacement modernization of older pre-existing structures.

Keeping the foregoing in mind, it will be appreciated that the present invention while retaining the most desirable features of prefabricated window and frame structures, also obviates the less desirable structural features thereof, discussed above. Thus, in accordance with certain of the more salient features of the present invention, which will be subsequently described in particular detail, there is provided-in conjunction with a sliding or sashtype window and frame structure of the type which, in addition to being capable of utilization with a unitary and dimensionally stable outer frame structure, is adapted to permit and facilitate temporary removal of the various panel components, or members, within the frame structure after installation thereof in a building-wall window opening, sash balance means which facilitates substantially effortless sliding movements of the assembled sash panels even in large size installations such as in office buildings, and the like. Consequently, even though the panel components may be readily removed from the frame structure for cleaning and repair purposes, the window panels also are capable of being effortlessly shifted to and safely remaining at any selected alternative position within their respective guide tracks ranging between the fully open and fully closed positions. In this latter regard, in the more preferred structural aspects of the present invention the frame structure is constructed as a prime window structure in which to accommodate three panel components, such as an upper and lower window panel and a screen panel.

With these and other features in mind, .it is accordingly a principal objective of the present invention to provide a sash-type window and frame structure which may be prefabricated and quickly installed in a building-wall window opening with a minimum amount of adjustment or customizing of the structure being necessitated at the time and site of installation.

Another objective of the present invention is to provide a window and frame struclure capable of accomplishing the foregoing objective and wherein the frame structure can be fabricated as a unitized structural member prior to arrival thereof at the site of installation.

Another objective of the present invention is to provide a window and frame structure capable of accomplishing the foregoing objectives and which also possesses structural features permitting the window or panel components, after installation, to be readily removed and reassembled within the frame for purposes of repair and maintenance, or the like.

A further objective of the present invention is the provision of a window and frame structure for accommodating sliding or sash-type panel components and which is characterized by the inclusion of means for providing an effective insect and weather barrier between the panel components.

A more particular objective of the present invention is the provision of a frame structure for sash-balanced sliding window and screen panel components which is effective to retain the panel components in snug assembled relationship, and which also facilitates easily managed manual removal and reassembly of the panel components by the simple expedient of manually exerting slight lateral pressure and pivoting movement upon the panel components to permit the same to be snapped into and out of assembly with the frame.

Another particular objective of the present invention is the provision of a frame structure for housing sashtype panel components and which is characterized by sash balancing means, and by guide tracks on opposite sides of the frame wherein the sash-balanced panel components may be housed in assembled relationship within the frame for slidable movements between raised and lowered positions, and which is further characterized by the provision of structure whereby at least one of such guide tracks is resiliently and laterally displaceable to enlarge the medial opening or compartment wherein the panel components are housed, to thereby accommodate convenient assembly and/or disassembly of the panel components from the sash balancing means and the frame structure as a consequence of pressing the panel components laterally against and depressing said displaceable guide track.

Still another particular objective of the present invention is the provision of a sash panel guide track which is designed to carry the sash balancing means and to fit within the frame structure in snap-fit removably assembled relationship, whereby to accommodate easy accessibility to and removal of the sash balancing means for such purposes as convenient repair and replacement thereof.

Still another objective of the present invention is the provision of a sash panel guide track which in addition to having the characteristics of the last-mentioned objective also is designed to be resiliently displaceable while assembled within the frame siructure and thereby also accommodate convenient assembly and/or disassembly of the panel components as a consequence of pressing the panel components laterally against and resiliently and temporarily depressing the sash panel guide track within a channel opening in the frame structure.

Still another particular objective of the present invention is the provision of adjustable frame mounting means adapted to strengthen the frame structure and fortify the frame structure against damaging distortion during and after installation in a building wall opening.

Other and additional objectives, features and advantages of the present invention will become readily apparent to those ordinarily skilled in the art from the following detailed description taken in conjunction with the annexed sheets of drawings, on which:

FIG. 1 represents a perspective view of an assembled, prefabricated, sash-type window and frame structure embodying a preferred form of the present invention, and depicting, with portions 'broken away for clarity of illustration, the interior aspect of the assembly as it would appear when installed and viewed from the interior-wall side of a building-wall window opening; and

FIG. 2 is a perspective view of one of the inner peripheral walls disassociated from the assembly; and

FIG. 3 is an enlarged fragmentary representation showing, in partly isolated manner, a portion of the sash balancing means of the present invention in cooperative association with one of the window panels; and

FIG. 4 is a schematic fragmentary view showing certain functional aspects of the sash balancing means when engaged by a window panel, such as when the sash balancing means and window panel are associated in assembled relationship within a frame structure, as in the manner illustrated in FIG. 1; and

FIG. 5 is a view generally similar to FIG. 4, but for comparative purposes illustrating the functional aspects of the sash balancing means when disassociated from the window panel; and

FIG. 6 represents an enlarged, fragmentary sectional view of the upper window in closed relative position and received within the upper window guide track running along the top section of the frame structure; and

FIG. 7 is an enlarged, fragmentary view showing another feature embodied in the present invention.

PREFERRED EMBODIMENTS OF THE INVENTION In accordance with one preferred embodiment depicted in the drawings, the present invention is best exemplified in FIG. 1 as being embodied in a prime window and combination frame structure which is designated generally b" the reference numeral 10. The embodiment exemplified in the drawings, of course, is merely one of preference an I it should be recognized that although various structural features of the present invention which are embodied therein may be individually or completely incorporated, or embodied, advantageously in other types of sliding or sash-type window and combination frame structures, such as combination storm windows and frame structures and the like.

Briefly, the general organization of the window and frame structure 10 is such that an outer frame 11 of conventional rectangular configuration affords a stable peripheral encasement in which to arrange and orient the various window and frame components in assembled relationship. As illustrated, the rectangular frame 11 forms an annular housing which is shaped to receive and house the panel components, such as a screen panel 13 and exterior and interior window panels 14 and 15, respectively, for slidable movements between alternative raised and lowered relative positions. Means for mounting the frame structure in a 'building wall opening are provided such that the installed unit may readily serve in either newly constructed installations or, as a replacement window structure, in older installations. Such mounting means includes a sectionalized peripheral mounting flange 16 which is preferably fabricated from durable, high strength, light weight metal such as aluminum, or the like. The mounting flange 16 is shaped to define a generally inverted T-shaped cross sectional configuration, and, as mentioned, is sectionalized to provide interconnectable peripheral sections such as top section 16a, bottom section 16b, and oppositely facing intermediate side sections 160 and 16d. The oppositely disposed leg portions 16e and 16 of each of the sections are snugly received within oppositely facing interspaced channels 17a and 17b integrally formed on opposite marginal edges on the exterior side of the outer peripheral wall 19 of the frame 11 and extending continuously around the frame.

The relative interspacing of the channels 17a and 17b being such with respect to the oppositely disposed leg portions of the mounting flange sections as to permit one of such leg portions to be received throughout its length within one of the channels and thereafter shifted laterally, or sideways to insert the opposite leg portion in the other channel. When thus positioned the oppositely disposed leg portions 16c and 16f of each of the mounting sections span the space between and nest within the channels. At each longitudinal end of each of the mounting sections, the stem or upright medial leg 16g projects axially beyond the frame and is interconnected with a like portion of another mounting section on the adjacent side of the frame. Such interconnection may be provided by suitable fastening means such as rivets, or the like, rigidly securing the ends of the adjacent mounting sections together through alignment slots, such as at 16h at each of the overlapping corners of the mounting sections.

The frame 11, for such purposes, among others, of providing substantial strength, light weight construction and minimization of material, is designed and fabricated in such manner that it possesses a hollow core structure. The hollow structural characteristics of the frame are provided, in part, by the outer peripheral end wall 19 and spaced parallel exterior and interior side walls 22 and 23, respectively, which interconnect with the end wall 19 and an inner peripheral wall 25 on which panel guide tracks are defined. The inner peripheral wall 25 may be formed integrally with the top and bottom sections of the frame. However, at least one of the side sections of the inner peripheral Wall 25 constitutes a laterally movable or floating guide section.

As best shown in FIG. 1, such a floating guide section is depicted as being carried within the right-hand side of the frame 11 and is identified by the reference numeral 27. As illustrated, the floating guide section 27 rides upon resilient means disposed between the floating guide section and the outer peripheral end wall 19 and is confined in assembled relationship with-in the frame 11 by oppositely facing shoulders 28 and 29 projecting towards each other from opposite sides of the exterior and interior side walls 22 and 23, respectively, and which serve to abut against opposite marginal edges of the inwardly facing side of the floating guide section and confine the same in a recessed location between the side walls 22 and 23.

At its opposite longitudinal ends, the floating guide section 27 is adapted to interlock with the non-floating top and bottom sections of the inner peripheral wall and, as best viewed in FIG. 2, by the ribs 34 and 35 on the floating guide section being notched at each opposite end to provide grooves, as at 36a, 36b, 37a and 37b, to receive, as in upper corner of FIG. 1, the normally disposed, adjoining ends of the top and bottom sections, respectively, of the inner peripheral wall in tongue and groove relationship.

The resilient means, upon which the floating guide section 27 rides, may comprise one or more resilient members which are shown as being in the form of an arched spring 40, such as may be fabricated into a generally U-shaped configuration from a thin sheet or strip of resilient metal, plastic, or similar material. The arched springs are, as the one indicated primarily by broken lines in FIG. 1, arranged between the outer peripheral end Wall 19 and the oppositely facing surface of the floating guide section 27, and are disposed so that they will spread and retract lengthwise of the panel guide section. When so arranged, the arched springs 40 bias the floating guide section 27 inwardly towards the inner end portions of the side Walls 22 and 23 and against the shoulders 28 and 29. To .insure that the arched springs will not shift or slip towards the bottom end of the panel housing 12, offset projections, not shown, may be provided on the arched outer surface of the springs which will grip the underside surface of the floating panel guide section 27, or outer peripheral end wall 19, and hold the arched springs in place.

By virtue of the floating panel guide section 27, the window and screen panels may be readily removed from the panel housing for cleaning, storage or repair of broken glass, damaged screening and the like. To effect insertion or removal, each panel is slipped sideways into its intended track and manually pressed against the floating guide section 27 with sufiicient pressure to depress the spring member sufficiently to permit the opposite side of the panel to pass into and be located in its appropriate panel guide track. Thereafter, of course, when the panel is properly aligned with its respective track, the pressure upon the spring 40 is released and the floating guide section will be resiliently urged into position and retained in assembly within the panel housing. Obviously, the same procedure is capable of being repeated for insertion or removal of each of the panel components. During assembly, the exterior panel, of course, would be inserted first, followed by insertion of the intermediate panel and thereafter by insertion of the interior panel. Conversely, when it is desired to remove the panels, the interior panel would be removed first, followed by removal of the intermediate and exterior panels.

The foregoing structural description is descriptive of a type of basically prefabricated window and frame structure more particularly described in my US. Patent No. 3,360,030, issued Dec. 26, 1967. The last-mentioned patent however primarily pertains to prefabricated sashtype window and frame structures of the type commonly referred to as combination storm window and frame structures. By way of distinctive improvement the present invention provides features, to be hereinafter more fully described, which although readily adaptable to window and frame structures of the combination storm window variety are particularly suitable for, among others, prime window types of prefabricated window and frame structures. In this regard, one such particularly significant structural feature of the present invention resides in the provision of structure designed and arranged to function as sash balancing means in combination with a prefabricated window and frame structure having at least one movable wall section, or floating guide section, which is preferably either of the foregoing type or of the gen eral character of that described in my earlier mentioned patent. Such combination structural features are best depicted in FIG. 2, wherein it will be observed that the interior and exterior window guide tracks 31 and 32 of the floating guide section 27 are provided respectively 1 With medial longitudinally disposed sash balance guide gitudinally extending compartments such as compartments 42 and 43, respectively communicating with the guide slots 38 and 39. Loosely housed within the cornpartments 42 and 43 are panel counterbalancing means, which are depicted in the preferable form of elongated coil springs 51 and 52, each of which is suitably secured at the top or upper end portion of the floating guide section 27 by means of rivets or other conventional means of securement.

Riding within each of the guide slots 38 and 39 there is a spring clutch mechanism respectively designated as 60. In a manner to be subsequently described, the spring clutch mechanisms are interconnected with the otherwise free ends of the coil springs 51 and 52 and are designed to travel smoothly within the guide slots together with raising and lowering movements of the window panels 14 and 15 within the guide tracks of the prefabricated frame structure 11. Conversely, when the window panels are disassociated from assembly with the frame, the spring clutch mechanisms are designed to lock in a stationary position within the guide slots 38 and 39. The relative functional aspects of the travel position and locked position of each of the spring clutch mechanisms is the same and accordingly the ensuing description of such functions, in avoidance of duplication of description, will be limited to one of the spring clutch mechanisms such as the spring clutch mechanism 60 for the lower interior window panel 16; keeping in mind that such description is also applicable to the spring clutch mechanism for the upper exterior window panel 14.

Keeping the foregoing in mind, FIG. depicts the spring clutch mechanism 60 in its locked position, whereas FIGS. 3 and 4 conversely depict the spring clutch mechanism in its unlocked or released position. The spring clutch mechanism includes a generally hollow body portion 62 arranged to ride within the compartment 42; an elongated rocker arm 63 medially pivotally carried, as at 64, alongside the body portion and in position aligned to clear and project endwise through the guide slot 38 and bring the tapered end surface of the inwardly projecting end portion, or clutch releasing end 65, into the path of travel of the window panel when the latter is properly assembled within the guide track 31; a spring plate 66 housed within the body portion and biasing the rocker arm towards a normally locked position with the outwardly disposed end thereof, in the form of a wedging end 67, pivotally biased into wedged contact with the interior wall surface of the compartment 42; a panel suspension arm 68 laterally offset from the body portion and also aligned to project through and ride or travel within the guide slot 38; a spring connection end in the form of a hook-shaped hanger 70 projecting from the upper end of the body portion and arranged to hook onto the lower end of the coil spring 51 and suspend the spring clutch mechanism 60 within the compartment 42 in the manner described and also to transfer tension exerted :by the coil pring through the spring clutch mechanism to the panel suspension arm 68 when, as shown in FIGS. 3 and 4, the wedging end is pivotally retracted away from the wall surface of the compartment 42. In this latter respect, the tension imparted from the coil spring 51 also cooperates with the leaf spring 66 by increasing the overall biasing force of the wedging end 67 against the wall surface of the compartment 42 when, as shown in FIG. 5, the window panel 15 is disassociated or removed from the guide track 31.

When, as illustrated in FIGS. 3 and 4, the window panel is properly assembled within the frame 11, it is assembled in such manner that the panel suspension arm 68 is received axially within an opening provided therefor in the open end of the bottom sash 15a of the window panel 15. As best observed in FIG. 3, the last-mentioned opening is preferably defined by forming the bottom sash as a substantially hollow, light-weight, sash member with a strengthening partition wall 69 spanning the hollow interior of the bottom sash in spaced parallel relationship with the lower end surface thereof and defining a tubular opening in conjunction therewith stretching lengthwise of the bottom sash. Moreover, the partition wall 69 is arranged to abut against and depres the clutch releasing end 65 of the rocker arm 63 thereby resiliently overcoming the outwardly biasing and wedging influence of the spring plate 66 and coil spring 51 upon the rocker arm wedging end 67 and thereby causing the latter to rock or pivot to a position, as shown in FIGS. 3 and 4, free of engagement with the wall surface of the compartment 42. In such position, referred to as the travel position, the spring clutch mechanism is free both to travel within the guide track and to transfer the tensional lifting effects of the coil spring 51 to the window panel and counterbalance the weight of the latter; the coil spring of course :being selected to provide a tensional force coordinated to counterbalance the gravitational force, or weight, of the particular window panel employed in a given type of window and frame assembly.

By virtue of the manner of construction of the frame 11 and the floating guide section 27, the floating guide section together with both entire spring clutch mechanisms may be quickly and conveniently assembled into and removed, without need of working tools, from the frame as one complete unit. Moreover, such assembly and/or removal can be accomplished in the same manner either before or after installation of the frame in a building wall. Thus, repair or replacement of either the floating guide section 27 or the spring clutch mechanisms can be effected easily and inexpensively. In this respect, while it is preferred that both the frame 11- and the floating guide section 27 should be constructed from a rigid yet somewhat flexible plastic material having the physical characteristics obtainable from a rigid polyvinyl chloride molding composition, either one or the other may be so fabricated as to be sufiiciently flexible, without undue sacrifice of strength and rigidity, to permit the floating guide section to be snapped into or out of snap-fit confined assembly within the frame 11. Thus, for example, fabrication of either frame or the floating guide section, or both, from a rigid polyvinyl chloride, or like structural plastic materials has been found to afford adequate distension of the frame, constructed as shown, to permit manual assembly or disassembly of the floating guide section. Similarly, fabrication of the floating guide section from a rigid polyvinyl chloride molding composition has imparted sufiicient flexural properties thereto that the floating guide section may, without damage, be flexed adequately to snap into a rigid relatively inflexible frame 11.

Although not necessary to the functional operability of the sash-balanced window and frame structure described, it has been found desirable in many instances to utilize means for implementing the overall counterbalancing of the upper exterior Window panel 14 when the latter is stationed in its uppermost or normally closed position within the frame 11. Such implementation is accomplished by what is believed to be a unique and highly effective manner, best observed in FIG. 6. As shown, the top sash portion 14a of the window sash panel includes, preferably on the interiorly facing side, an integrally formed and generally C-shaped slot or groove at 14b extending lengthwise of and along the upper marginal panel guide track at the top of the frame 11 and which is the top frame guide track counterpart of the guide track 32 provided on the floating guide section 27. Stuffed or Otherwise placed and snugly retained within the groove 14b is a conventional, soft, weather stripping material such as a strip of wool pile 72, or the like, which projects from the groove and presses firmly against the side of the guide track and an underlying panel facing bead, or lip 73, protruding from and running lengthwise of the gulde track entranceway. Thus, when the upper window panel is fully raised to its normally closed position the soft protruding portion of the pile 72 snaps into position above the lip 73 and in addition to providing a weather barrier at such location also ideally supports a small portion of the window Weight, which small portion of support, when related by way of implementation of the tensional support also being provided by the sash balancing mechanism, is of substantial benefit and significanoe, Moreover, the restriction to movement of the upper window panel offered by such structure, while be/ ing substantial in relation to retention of the upper window panel in its normally closed position, is essentially unrestrictive of substantially effortless opening and closing movements of the upper window panel 14.

Another unique structural feature of simple and efficient design which provides the assembly with improved weather-tightness along the bottom section of the frame is most clearly depicted in FIG. 7. As illustrated, a weather proofing mounting strip or riser strip 75 is designed to snap into a C-shaped upwardly opening groove 76 on the bottom section of the frame 11 and defined between a pair of parallel upstanding ribs 77 and 78 rimming the interior edge of the inner peripheral wall 25. The riser strip 75 when in assembled position forms an upwardly standing extension of the last-mentioned ribs along the full length of the inner peripheral wall and includes a longitudinal C-shaped groove or slot 79 retaining weather stripping in the upstanding portion which opens towards the Window guide track accommodating.

the lower interior window panel; and a longitudinally extending depending lug portion 80 designed to snap into and firmly secure the riser strip within the groove 76. As shown, the weather stripping 81 fits into and is retained within the groove 79 in such manner as to press against the bottom interiorly facing side of the lower window panel 15 when the latter occupies its lowered closed position. Moreover, the riser strip 75 acts as a barrier to preclude overflow of water over the interior side of the frame without necessitating a dimensional increase in the transverse dimensions of the frame. In this respect, it will be appreciated that an increase in the transverse dimensions of the bottom section of the frame would also necessitate a matching increase in all of the remaining sections of the frame. Further, a comparable increase in the side wall sections would produce a twofold reduction in the spacing between the side sect ons of the frame and interfere with the removabiilty and/r assembly of the window and screen panels.

As a consequence of the improved characteristics and structural nature of the present invention, it has been found that a window and frame structure of the type herein described may, with the exception, of course, of the glass windows, screening material, T-shaped peripheral frame and portions of the sash-balancing mechanism be fabricated entirely from a relatively low-cost extrudible plastic composition. Among numerous other plastic compositions, a rigid polyvinyl chloride plastic molding composition has been found to be particularly suitable and is capable of being extruded to conform to relatively exacting dimensional and configurational specifications and of having extremely good weatherability under the varying weather conditions to which storm windows are ordinarily subjected. Additionally, extrudible polyvinyl chloride molding compositions of the rigid-type are readily obtainable which will produce extrusions of most any desired color including white, which, of course, in the manufacture of prefabricated windows, is the most preferable color to the ultimate purchasing customer.

Another advantage resulting from the use of a plastic frame construction is that the frame 11 inclusive of the window and screen may be extruded in dimensionally uniform sect ons and readily united into a composite unitary structure by conventional and highly economical methods. Furthermore, the union of the plastic sections can be carried out at the fabricating site where suitable tools and machinery can be most effectively employed to insure proper permanent alignment and orientat on of the frame assembly. As a consequence, a subsequent saving in labor and cost involved in the installation and adjustment of the frame in a building-wall window opening is achieved. Additionally, the essentially unitary nature of the assembly makes it quite rugged and far less susceptible to damage or repair after once being installed.

In addition to the above highly desirable features, the window and screen panels are readily removable from the interior side for such desirable purposes as to accommodate cleaning and replacement of broken window glass or damaged screening. Moreover, and in most unusual fashion the removable window panels are also counterbalanced to permit relatively effortless opening and closing movements thereof as well as intermediate movements to most any desired position. Hence, unlike most prefabricated window and frame assemblies, the prefabricatable window and frame structure of the present invention affords a versatile, durable and economical light-weight assembly which is well-suited to large as well as small window installations.

It will, of course, be understood that the foregoing description is exemplary only of a preferential embodiment and that various details of construction may be modified through a wide range without departing from the principles of this invention.

I claim:

1. A prefabricated window frame structure comprising:

a unitized frame structure peripherally defining a panel compartment for housing at least one window panel for endwise sliding movements within said panel compartment, and;

interspaccd mutually facing panel guide tracks carried in assembly with said frame structure on opposite sides of said panel compartment in which to accommodate and retain opposite sides of said window panel in assembly for endwise track guided window movements between raised and lowered relative positions within said frame structure, at least one of said panel guide tracks being retained within said frame structure for shiftable resiliently biased movements relative to the other of said panel guide tracks to vary the assembled interspacing therebetween and whereby to accommodate removable assembly of said window panel with said guide tracks and said frame structure;

in combination with sash balancing means carried within said frame structure, said sash balancing means including suspended spring tension means, a panel suspension arm sus pended from said spring tension means for tensionally biased movement in a path running lengthwise of and adjacent to one of said guide tracks, said panel suspension arm being insertable in sleeved relationship within a tubular side opening in said window panel and transferring spring tension thereto from said spring tension means for counterbalancing said window panel during and throughout guided movements thereof between alternative raised and lowered positions within said guide tracks,

a clutch mechanism carried by said sash balancing means and interconnected with said panel suspension arm, said clutch mechanism having means for releasably locking said panel suspension arm in positively retained position relative to said adjacent one of said guide tracks when said window panel is disassociated from assembly therewith, said clutch mechanism including a pivotally mounted rocker arm having a clutch releasing end and a pivotally opposite wedging end, spring means for resiliently pivoting said wedging end pivotally into wedged contact with said adjacent one of said guide track when said window panel is disengaged from said panel suspension arm,

and said clutch releasing end being pivotally engageable with an edge surface of said window panel to pivot said Wedging end out of wedged contact with said adjacent guide track when said window panel is engaged with said panel suspension arm to accommodate assembled raising and lowering movements of said window panel within said guide tracks.

2. The combination, as defined in claim 1, wherein said shiftably retained panel guide track is removably assembled in snap-fit relationship within said frame structure.

3. The combination, as defined in claim 2, wherein said sash balancing means is carried by and removably assembled as a combined unit with said shiftably retained panel guide track.

4. The combination, as defined in claim 3, wherein one side of said shiftably retained panel guide track defines a guide track arranged to accommodate and guide said window panel for endwise sliding movements between relatively spaced open and closed window positions, and wherein said spring tension means is positioned on the opposite side of said shiftably retained panel guide track in the form of a coil spring suspended for tensionally counterbalancing engagement with said window panel.

5. The combination, as defined in claim 4, wherein said shiftably retained panel guide track defines a guide slot furnishing open communication between said opposite sides of said shiftably retained panel guide track and extending axially lengthwise of the said guide track defined thereon, and wherein said panel suspension arm rides suspended from said coil spring in said guide slot for removable engagement with a bottom portion of said window panel when the latter is assembled in said frame structure.

6. The combination, as defined in claim 1, wherein said frame structure is fabricated from an essentially rigid plastic molding composition.

7. The combination, as defined in claim 1, wherein said shiftably retained panel guide track is fabricated from an essentially rigid plastic molding composition.

8. The combination, as defined in claim 1, wherein said tensional supporting means comprises a coil spring.

9. A prefabricated Window frame structure as defined in claim 1, wherein said frame structure includes an integral bottom section provided with an inner peripheral wall bridging between the exterior and interior sides of the frame structure, weather proofing means attached to said bottom section of said frame structure and running along the length of the inner peripheral wall thereof at a location adjacent said interior side, said weather proofing means being in the form of a riser strip of uniform cross-sectional configuration throughout the length thereof; said riser strip comprising an upper marginal portion seating upon and rising from said inner peripheral wall and having means for carrying a weather stripping material in facing relationship with said panel compartment, a lower marginal portion engaging said bottom section of said frame in secure snap-fit tongue and groove relationship and locating said upper marginal portion in position to press said weather stripping material against and frictionally resist raising movement of said window panel when the latter occupies a fully lowered position within said guide tracks, said weather stripping thereby providing a weather seal and also assisting in retaining said window panel in fully lowered position.

10. A prefabricated window frame structure as defined in claim 1, wherein said frame structure includes an integral top section provided with an inner peripheral wall having parallel interspaced ribs defining an upper guide track, one of said ribs having a longitudinally extending bead partially restricting the entranceway to the guide track defined in said top section; and

wherein said window panel includes flexible weather stripping along the upper edge thereof arranged to seat within said upper guide track and yieldably bear against said head when said window panel occupies a fully raised position within said guide tracks, said weather stripping thereby providing a weather seal and also assisting in retaining said windowpanel in fully raised position.

References Cited UNITED STATES PATENTS 1,357,569 11/1920 Jones 49-437 X 2,791,795 5/1957 Haas 49--446 X 2,841,834 7/1958 Poole 49489 X 3,124,849 3/1964 Osten 49-430 X 3,239,892 3/1966 Johnson 49430 X 3,377,747 4/1968 Donkin 49-414 FOREIGN PATENTS 723,420 12/1965 Canada.

DAVID J. WILLIAMOWSKY, Primary Examiner P. C. KANNAN, Assistant Examiner US. Cl. X.R. 49-380, 446, 489 

